Why Are Hedgerows So Important?

By Izzy Williamson

What is a hedgerow?

Also known as “the patchwork quilts of the British countryside”, hedgerows are strips of wildlife habitats which lie along a woodland edge1. They tend to be found lining roads, railways, footpaths, and fields. While hedgerows can vary from narrow hawthorn bushes, to thick brambles and mature trees, they tend to be over 20m long and less than 5m wide.

Why Are Hedgerows So Important?

Why are hedgerows important to wildlife?

Food and shelter:

Hedgerows and their associated trees, banks, ditches, and margins, provide valuable nesting, pollination, shelter, and migration opportunities for many woodland and wildlife species. The loss and degradation of over 75% of hedgerows since 1960 has therefore represented a major threat to ecosystem health2.

Conservation:

The UK Biodiversity Action Plan has identified 130 priority BAP species significantly associated with hedgerows – of which 13 consist of flagship species. Over half of these (56%) are dependent upon hedgerow trees3.

Water and soil regulation:

Hedgerows help reduce soil erosion, water run-off, and flooding.

Why are hedgerows important for the climate?

Hedgerows are an active carbon sink. They sequester carbon in wood growth above ground, in roots, in leaf litter as well as in other soil organic matter.

Hedges running across slopes can also capture eroding soil organic carbon from up to 60m uphill.

An estimated carbon sequestration rate of 1km of well-managed hawthorn hedgerow: 3.24t C/year.

Hedgerows are a carbon store. Although this depends on vegetation type, hedge structure, and management practices4, as an estimate, the carbon stock of UK hedgerows ranges between 15 tonnes C/ha for short hedges (1.5m), and 30-40 tonnes C/ha for tall hedges (2.7m). A similar carbon quantity is also stored in below-ground biomass.

Hedgerows are becoming a climate action area. In the Climate Change Committee (CCC) 2019 report, extending hedges by 40% is proposed as a key change required to reach net zero carbon by 2050. This would require the creation of 200,000km of new hedges5 the equivalent to 50% of England’s current road network.

Why Are Hedgerows So Important?

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Why Are Hedgerows So Important?

How to effectively manage hedgerows?

With appropriate management, the carbon sequestration rate and storage potential of hedgerows can be maximised. This can be achieved through the following:

  • Encourage biodiversity and native shrubs in the hedgerow. There is a positive relationship between more diverse hedgerows and soil organic carbon stocks.
  • Plant and encourage trees to grow in hedgerow. This will increase long-term carbon storage – especially if tree species are chosen according to sequestration rate and climatic suitability in future years.
  • Allow the hedge to grow. Minimising cutting to every 2-3 years6. Raising the height of hedgerows from 2m to 2.7m is estimated to sequester 2.0 Mt more carbon in hedge biomass across England and Wales7.
  • Restore damaged hedgerows. Maintain hedgerow health throughout the management cycle8.
  • Plant new hedgerows. Plant along existing boundaries, and fill in gaps in existing hedgerow network.
  • Use hedges as a renewable fuel. Use coppice hedgerow trees for wood fuel. Carbon gains from this could prove higher than allowing hedges to grow larger. The wood can either be used directly in log-burning stoves or chipped for use in biomass burners and boilers.

What funding is available?

Planting new hedges grant – BN119

  • Standalone capital grant as part of Countryside Stewardship Scheme.
  • £11.60 per metre. The payment rate is for the total length of boundary under the option.
  • Must be carried out between 1/11 and 31/03.
  • Plants must be 2 year old transplants and native species.
Why Are Hedgerows So Important?

Available on one of the following:

  • Sites of former hedgerows – as shown on historic maps or other records.
  • Sites where creation would extend or link existing lengths of hedgerow.
  • Sites where creation will help reduce soil erosion and runoff.
  • Sites close to slurry or digestate stores, livestock housing or free-range areas for poultry or pigs where creation will help capture ammonia emissions.

MOREhedges programme10

  • Run by The Woodland Trust.
  • Will subsidise up to 75% of cost of planting 100-250 metres of new hedgerows, allowing a large tree to grow every 6m.
  • Available to landowners and farmers.
  • Only eligible if the hedgerow either connects directly with at least 0.2ha of existing/newly planted woodland OR connects to existing hedgerows that connect to woodland.
  • Funding can be provided for up to 1000m hedging.
  • Must commit to the care and management of the hedgerow for at least 30 years.

The Tree Council12

  • A charity open to donations through the Community Grants Programme.
  • Also open to corporate partnerships with regard to hedgerow planting and maintenance.

Bibliography

  1. https://www.nationalgeographic.org/article/hedging-biodiversity/
  2. https://www.hedgelink.org.uk/cms/cms_content/files/89_hedgerow-survey-handbook.pdf
  3. https://www.sciencedirect.com/science/article/pii/S030147970090358X?via%3Dihub
  4. https://www.cfeonline.org.uk/environmental-management/climate-change-mitigation/carbonstorage-and-sequestration/hedgerows/
  5. https://www.theccc.org.uk/publication/net-zero-the-uks-contribution-to-stopping-global-warming/
  6. https://hedgelink.org.uk/hedgerows/hedgerow-biodiversity/
  7. http://publications.naturalengland.org.uk/publication/5419124441481216
  8. https://www.hedgelink.org.uk/cms/cms_content/files/78_hedgelink_a5_12pp_leaflet_7.pdf
  9. https://www.gov.uk/countryside-stewardship-grants/planting-new-hedges-bn11
  10. https://www.woodlandtrust.org.uk/plant-trees/large-scale-planting/morehedges-faqs/
  11. https://treecouncil.org.uk/take-action